AIM: To evaluate the effect of corneal graft diameter on therapeutic penetrating keratoplasty (PKP) for fungal keratitis. METHODS: A total of 116 patients (116 eyes) suffered from fungal keratitis underwent PKP at the Affiliated Hospital of Medical College Qingdao University from May 2006 to May 2010. They were divided into two groups according to the corneal graft diameter. 64 eyes’ corneal graft diameter was 8.00mm or larger and 52 eyes’ graft diameter was smaller than 8.00mm. The follow-up time was 2 years. The postoperative visual acuity and complications were documented and compared. RESULTS: Sixty-two (96.88%) eyes and fifty (96.15%) eyes preserved eyeballs respectively in two groups. There was no statistical difference in postoperative visual acuity (P=0.961), corneal graft clear rate (P=0.132) or the incidence of recurred fungal infection (P=0.770) between two groups. But there was a higher incidence of graft rejection (P=0.020) and secondary glaucoma (P=0.039) in group with corneal graft diameter 8.00mm or larger. CONCLUSION: PKP is an effective treatment approach for fungal keratitis. There is a higher incidence of complications in large-diameter PKP for fungal keratitis. Effective, preventive and therapeutic measures can improve the prognosis.